Setup and installation of operating systems and other complex computer applications may be complex and sometimes time consuming. In some cases, a computer system may halt when a problem is encountered during a setup or installation process, especially during installation of an operating system because the installation is at a low level where error trapping and recovery functions may not be available.
As operating system and complex computer applications become ever more complex, the time to install can become quite lengthy. If an error causes a problem during installation, a user may become frustrated if the installation is restarted from the beginning.